Seasonal variation of atmospheric total gaseous mercury and urban air quality in South India

This study analyses seasonal and regular variations in ambient atmospheric concentrations of total gaseous mercury (TGM), ancillary air pollutant concentrations, and their relationship to weather conditions of a megacity environment in India. Further, to correlate with TGM concentrations at different megacities all around the urbanized environments in the world. The average concentration for TGM was 4.66 ± 8.35 ng/m3 and with an absorptions range of 0.41∼540 ng/m3 throughout the study period. The maximum concentration of total gaseous mercury was observed at 5.64 ng/m3 during the winter, while the minimum concentration was 3.91 ng/m3 during the southwest monsoon. The multivariate statistical analysis indicates the TGM values interacted positively with SR, WD, BP, CO, PM2.5, NO2, NOx and negatively with SO2, relative humidity, wind speed, and temperature. Meteorological parameters have an essential influence on the transport and distribution of pollutants in the monitoring site due to its location, local sources, and anthropogenic activities. Wind across India belongs to the southern hemisphere in summer and to the northern hemisphere in winter due to the movement of the intertropical convergence zone. Limited studies of atmospheric mercury concentrations have been conducted in India's city environments; however, as far as our results are concerned, they are the essentials, which exposed about environmental aggregate vaporous mercury detected in a required industrialized and coastal metropolitan zone in India.